Is it legal to have someones name on your website and state they have created lies about your website?
I don't think it's illegal to name someone, but problems could arise if you accuse them of something (spreading lies about your website) without any evidence.
Yeah, you're looking at civil issues if they say you are libeling their good name. Where are you from/where is the site hosted at? If any of those answers are the US look up the Privacy Act and see what is covered under it.